Apparatus and method for recording sound accurately



March 5, 1935. T. H. NAKKEN APPARATUS AND METHOD FOR RECORDING SOUND ACCURATELY 2 Sheets-Sheet 1 Filed May 27, 1930 INVENTOR .9 a g N w I m m THEOOORUS H. NFIKKEN ATTORNE\ March 5, 1935. T. H. NAKKEN APPARATUS AND METHOD FOR RECORDING SOUND ACCURATELY Filed May 27, 1930 2 Sheets-Sheet 2 Nt mm U Q R mm 8 n m rem an 5 9v Ev Iv X, mm J3 INVENTOR THEODORUS- H.- %2WA ATTORNEY HKKEN Patented Mar. 5, 1935 PATENT OFFICE APPARATUS AND METHOD FOR RECORDING SOUND ACCURATELY Theodorus H. Nakken, New York, N. Y., assignor to Nakken Patents Corporation, a corporation of Delaware Application May 27, 1930, Serial No.456,058

4 Claims.

This invention relates to the faithful recording of a sound theme such as a musical rendition or articulate speech, but of course, is not limited to any theme. More particularly, the invention relates to the making of faithful reproducible sound records is an improved manner and of an improved character.

Much work has been done in the recording of sound. In accordance with one method, sound is recorded photographically. In accordance with another method, it is recorded magnetically. In accordance with another method, it is recorded mechanically. Regardless of which of these methods of recording sound is employed, one large item of expense is that required to pay the artists who originate the theme, whether it be vocal or instrumental, and this expense is dependent upon the length of time such artists must be employed. Obviously, the desideratum in the making of a sound record is to produce a good record and this can not be determined in accordance with usual practice until the record is made, which often necessitates keeping the artists on hand or bringing them back for takeovers.

A photographic record can not be rendered until it is developed and a mechanical phonic line record can not be reproduced or rendered until it is made. If the intermediate wax record is tested by reproduction, there is a likelihood that such record be injured by reason of abrasion while a considerable time interval and possibly.

useless expense would be entailed if reproduction were delayed until permanent records had been reproduced from an initial wax record.

In connection with the magnetic records, it has been found that cross talk and deterioration quickly take place and such records have not come into commercial use.

In the mechanical fabricationof sound records, and in fact in many methods of recording sound, the necessity of moving parts of necessity possessing mass, introduces an obstacle on account of the high frequency to which such mass possessing parts must be moved when synchronously recording many sound themes.

In carrying out my invention, I objectively make possible a test of what has actually been recorded of a sound theme at the time of making the sound theme either contemporaneously and synchronously with its making or immediately .after its making and without in any way injuring the subsequent reproducing capability of such record. In addition, in carrying out my invention, I objectively eliminate all trouble and limitations imposed by reason of the inertia of moving parts.

More specifically, in carrying out my invention, I propose as an intermediate step in the making of a permanent sound record, the making of a magnetic record and the handling of such magnetic sound record at least temporarily in such a way as to maintain that record for the purposes of reproduction in accordance with my invention in perfect condition. By the utilization of this intermediate sound record, I make possible a reproduction of an actual sound record for the purpose of monitoring synchronously with the actual rendition of the theme being recorded and am thus in a position immediately after the rendition by the artists of a sound theme to know whether or not it is safe to discharge them.

I then propose the utilization of the magnetic sound record to make from, it mechanical or other records at such reduced speeds as to eliminate all distortion due to the inertia of necessary moving parts possessing mass. In carrying out my invention, it is a further objective to handle and temporarily store the magneticrecord in the steel wire in such a way as to prevent the creation of cross talk. In general, this requires the separation of every portion of such wire record from any other portion and I prefer to utilize storage drums and mechanism for winding the wire thereon in the form of separated convolutions.

The above and fmther objects of my invention will be pointed out more particularly in the accompanying claims which represent the sole limitation of what I claim and which are directed to the illustrative embodiments of my invention described in the following specification in connection with the accompanying drawings solely for purposes of illustration and not limitation.

In the drawings, Fig. 1 is a diagrammatic representation of apparatus capable of making my intermediate record and monitoring the same during its manufacture; and Fig. 2 is a diagrammatic representation of apparatus capable of making a permanent record from my intermediate magnetic record.

Referring now more in detail to the drawings, any suitable microphone 1 may be employed and positioned according to the best practice to respond to any of the usual sources of sound themes such as an orchestra, actors on a stage, vocalists, or in fact any of the producers of sound themes usually to be recorded. 2 indicates any and all the telegraphone.

necessary apparatus including a source of electric energy and amplification means capable of responding electrically to electric variations initiated by the microphone 1 and capable of imparting an energy variation to the circuit 3, 4 which corresponds in frequency and amplitude with that of the sound theme to be recorded. The coil 5 of an electromagnetic recorder 6 is energized by this circuit and may be of any approved form such as those described in connection with the Pulsen '7 is an electromagnetic pickup of any suitable type such as that disclosed in the Pulsen telegraphone. Its winding 8 serves as the input for the circuit 9, 10 leading to the apparatus 11 including a suitable source of electrical energy and a suitable amplifier mechanism to cause faithfully amplified electrical energy to be supplied by circuit 12; 13 to any suitable sound reproducer 14 whichis preferably located in a monitory room 15. The pickup '7 may be located close to the recorder 6 but preferably out of the magnetic influence thereof; 16 is a demagnetizer preferably supplied with energizing current from the controllable circuit 1'? and serves to demagnetize the wire or arrange the minute polarities of magnetization all in the same direction in the steel wire magnetic record part 18. This wire is supplied from a reel 19 and is drawn over guides 20, 21 and 22 with the guide 22 also serving if desired as a drawing or draft mechanism by reason of its belt connection 23 with the driving motor 24. After leaving the guide 22, the steel wire 18 is preferably wound on a drum 25 rotating on threaded trunnions 26 and 27 axially impelling the drum 25 by means of the threaded mounting crotches 28 and 29. The drum 25 may be driven in any suitable manner as by the belt 30 from any suitable source of power such as the motor 24. If the wire 18 is wound up on the drum 25, the threads 26 and 2'7 determine the spacing of the convolutions 31 which are arranged to be such as to maintain all contiguous parts of the convolutions spaced beyond the minimum space within which distorting magnetic effects are produced, commonly called cross talk.

The magnetic record is made on thiswire 18 and my apparatus differs particularly from a,

Pulsen record and Pulsen apparatus in that at no time are different localities of the wire permitted to touch or come into close association one with another. It is well known that no record quite so perfect as a sound theme can be made as that of a magnetic record but it is equally well known that no commercial success has attended this method of recording sound. My work has taught me that there is no practical method of maintaining for any great length of time in any reasonably small space a perfect magnetic record in any magnetic material dependent for its record upon locally varying magnetism. I therefore deliberately make no attempt to retain such records for more than the sufficient time to reproduce them in the form of a more permanent record but I have found that so long as different localities of steel wire bearing a magnetic record are kept apart to eliminate cross talk and distortion, that this magnetic record may be used for a number of reproductions without deterioration, and it is particularly adapted to monitoring the actual record made contemporaneously with the making of it so that the monitor may not only determine that the entire sound theme is poorly recorded and wipe out the magnetic record as with the magnetizing device 16 and have it immediately done over again, but it can stop the rendering equivalent.

second similar drum 25' both controlled as to their axial movement by the threaded trunnions 26 and 27 at any speed desired. It is preferred that the recording be made at a predetermined speed for purposes of synchronization with the permanent record to be made.

In the utilization of my record on the wire 18, useful apparatus comprises an electromagnetic pickup 40 connected by the input circuit 41, 42 to suitable amplifier apparatus 43, the output circuit 44 of which operates any suitable electromagnetic cutting tool 45, which of necessity includes a part possessing mass and therefore inertia. A wax record 46 is shown in operative relation to the cutting tool 45 and may be driven by any approved apparatus such as the turn table 47 from the gearing 48 while the worm feed 49 and gearing 50 operate the transverse feed of the cutting tool 45, all being driven by a suitable source of magnetic power such as the motor 51 through belts and pulleys 52 and 53 or their The same motor 51 may be utilized by suitablev belts and pulleys 54, 55 and 56 to draw the wire 18 operatively through the pickup 40 and rewind it on the drum from which it may be utilized again without deterioration. I preferably through the medium of the gearing and drives synchronize the cutting tool feed 49, the turn table 47 and the traverse of the wire 18 and by relative proportioning of the gearing, belts and pulleys may effect any desired spacing between convolutions of the phonic line 60 and any relative extent greater or less in length relatively .to the wire 18 of the phonic line carrying the same amount of sound theme. It is, of course, to beunderstood that I may as desired interchange and replace gears to effect variations in this proportionality at will. But I consider to be of most importance the fact that my apparatus carrying an easily reproducible perfect sound record in magnetism in the steel wire 18 may be reproduced at any desired slow speed and that this slow speed may be selected so that the movements of the'cutting tool or other part which must accord with sound vibratory movements need not move at a speed which causes distortion or interference due to inertia. By this apparatus I am not only able to cut a perfect phonic line in the wax disc 46 but it is no longer necessary for me to play this wax record to determine whether the recording of the sound theme was right or wrong. But I may reproduce it as a permanent phonographrecord without trouble from the mutilating effect of a reproducing stylus.

Also, I contemplate as an advantage of my apparatus that the amplifier apparatus 43 may include modulating means by means of which I may emphasize or suppress parts of the sound theme as they may be recorded on the wire 18, for example, if desired, I may super-amplify high frequencies. or the converse, reduce the amplitude of low frequencies. or in fact effect any of the now known methods of controlling an electric variation in carrying a sound theme and I may effect this by means of operators who have had time to study the actual record of the sound theme as it is in existence on the wire 18 and not be obli ed to do the same extemporaneously. I am therefore able actually to ime prove the second record over the first record from certain view-points even though the first record in magnetism on the wire 18 be an exact reproduction of the sound theme as produced by the artists.

Although'I have shown the apparatus which I employ diagrammatically, I desire it to be understood that I contemplate the utilization of apparatus in all its elements the best adapted for the functioning to be performed and as most of the individual elements going into my new method and new combination are well-known, I consider that a more detailed illustration would be confusing rather than helpful.

What I claim and desire to secure by United States Letters Patent is:

1. In the recording of sound themes of the type ultimately to be recorded as a phonograph record or photographic sound record on a film, first recording said sound theme magnetically upon a steel member at a predetermined rate of speed; simultaneously reproducing said magnetic record for the purpose of immediate censorship or monitoring; temporarily storing said magnetic sound record with parts bearing records of different sounds maintained free from mutual influence one upon the other, including maintaining said sound record in physical contact throughout its entire recorded extent with unyielding non-magnetic material andthe subsequent reproduction of said magnetic record in the form of a permanent record in apparatus for recording sound.

2. The means in combination including magnetic recording means, monitoring means, magnetic record storing means, magnetic pickup, amplifier and re-recording means suitable for practicing the method recited in claim 1.

3. In the recording of sound themes of the type ultimately to be recorded as a phonograph record or photographic sound record on a film, first recording said sound theme magnetically upon a steel member at a predetermined rate of speed; simultaneously reproducing said magnetic record for the purpose of immediate censorship or monitoring; temporarily storing said magnetic sound record with parts bearing records of different sounds maintained free from mutual influence one upon the other including maintaining said sound record in physical contact with unyielding nonmagnetic material; and the subsequent reproduction of said magnetic record in the form of a permanent record in apparatus for recording sound.

4. The means in combination including magnetic recording means, monitoring means, magnetic record storing means, magnetic pickup, amplifier and recording means suitable for practicing the method recited in claim 3.

THEODORUS H. NAKKEN. 

